"With the recovery of the U.S. economy, the U.S. UV/EB markets have rebounded significantly," said Paul Elias, business director of specialty products, Sartomer Company. "All sectors of UV/EB applications have improved and have resumed their upward growth curves. Although we are seeing some shift in production to Asia, particularly in the electronics markets, the overall UV/EB technology continues to expand at rates similar to the growth we experienced in the 90s."
According to Donald Dykes, president of Impact Marketing Consultants Inc. (IMC), U.S. consumption of UV/EB coatings for all applications in 2003 was estimated at 95 million pounds, valued at $370 million.
"With the economy in recovery, overall growth is forecast at six percent through 2008 when consumption will reach 120 million pounds, valued at $470 million," Dykes said.
As use of rad-cure coatings rebounds, suppliers of UV technologies are constantly working to develop products with increased performance characteristics to meet their customers' needs.
Bayhydrol UV XP 2420, a UV-curing, water-based polyurethane system from Bayer MaterialScience, is particularly suited for exterior wood paneling because of its outstanding weather stability, according to the company.
"Other than low price and consistent quality, our customers are looking for material that provides better outdoor weatherability properties, faster cure speed and materials for enhanced adhesion to plastics," said Elias. "Finding the balance of cost and performance for the specific application is always a factor."
Developing products for new rad-cure applications represents a great opportunity for suppliers. Emerging markets include food packaging, pressure sensitive adhesives, automotive coatings and DVD coatings and adhesives.
"We're focused on developing the next generation of UV-curable waterborne resins for wood and plastic substrates, new UV/EB applications such as coil coatings and automotive refinish and low odor and low extractable products for use in food packaging," said Bayer.
"Our technology department has been working on many emerging applications including optical display applications, UV/EB adhesives, and thermoformable UV/EB inks and coatings," said James Goodrich, senior applications chemist - graphic arts, Sartomer Company. "The new products being introduced by Sartomer are designed to meet the requirements of the new applications."
One area of focus is the optical display arena. "Our raw materials are being used in high-tech, UV/EB-cure coatings for highly engineered display components," said Elias.
Automotive applications have been the center of significant attention for the past couple of years, according to Elias, and UV ink jet is also attracting attention for graphic and industrial applications. "A committee that is addressing FDA-compliant UV and EB coatings has been very active within the RadTech organization," he added.
Suppliers to the rad-cure market have developed a number of new products to meet their customers' performance demands.
Cytec Surface Specialties supplies a full range of oligomers, monomer and additives. "We offer epoxy, polyester, amino, urethane and acrylic acrylates as well as a broad selection of monomers and additives for use in formulations," said Bayer.
Cytec Surface Specialties is offering Ebecryl 1040 UV monomer, a highly reactive urethane functional monomer that provides excellent adhesion to plastics; Ebecryl 113 UV monomer, a low odor monofunctional aliphatic acrylate with good adhesion to non-porous substrates; and Ebecryl 381 fluorocarbon acrylate, which provides excellent substrate wetting, particularly over oily surfaces and has minimal effect on the coefficient of friction, according to the company.
Sartomer manufactures a complete line of standard and specialty monomers, oligomers and photoinitiators. The low-VOC products are used in a variety of UV/EB coating systems, including automotive panels, wood coatings, packaging and concrete flooring.
The company has recently introduced many new monomers and oligomers designed for varied applications including UV/EB coatings and adhesives. New products for the UV/EB coatings market include CN2921 and CN2922, aliphatic urethane oligomers designed for outdoor applications such as automotive refinish and plastic coatings for electronics. "Both of these oligomers show excellent long-term weatherability and adhesion to plastic substrates," said Goodrich.
Wood products, such as paneling and prefinished wood flooring, comprise the third largest end use for rad-cure products, according to Impact Marketing Consultants.
Bayer MaterialScience has recently introduced a number of radiation-curing, water-based polyurethane systems for wood finishes. Bayhydrol UV XP 2420 is easy to apply and dries on wood within a few minutes. It takes only a few seconds under UV radiation for the finish to cure. Finishes formulated with UV XP 2420 can be either transparent or pigmented and are highly flexible, even at low temperatures, according to the company. They also have good chemical and mechanical resistance properties and exhibit outstanding weatherability. Applications include window frames and shutters, doors and exterior wood panels, according to the company.
Bayer MaterialScience also offers Bayhydrol UV VP LS 2282, which is suitable for clear and colored primers and topcoats, as well as Bayhydrol UV VP LS 2348 and Bayhydrol UV VP LS 2280. Bayhydrol UV VP LS 2348 exhibits outstanding adhesion and is suitable for use on furniture and parquet flooring. Bayhydrol UV VP LS 2280 was developed specifically for pigmented formulations and also adheres very well to metal.
On the equipment side, EIT's Instrument Markets manufactures a line of radiometers and on-line measurement equipment to help users determine if their UV curing systems are working optimally. Its latest product is 3DCURE, which allows users to measure any multi-dimensional or irregular-shaped object regardless of size.† With 3DCURE, users can obtain feedback from up to 32 UV sensors simultaneously and obtain joules/cm2 and watts/cm2 on any 3D part. The results can be viewed on the 3DCURE software.